Hi, @Leosimoni 

Thank you for posting on our business forum.

We generally do not recommend deploying EAP devices across multiple floors. While EAPs are equipped with omnidirectional antennas, thick floor structures can easily block wireless signals, which often leads to unstable connections between EAP units.

We would like to suggest that you run a test: please place the main AP and the two Client APs on the same floor, same room is best, and check whether the connection instability issue still persists.

If the test confirms the issue is caused by cross-floor deployment, we recommend that you consider adjusting your network layout accordingly.

Hi,  @Leosimoni 

Thank you for providing additional information, which has helped us gain a clearer understanding of the issue you are facing.

In some cases, client devices may fail to connect to the nearest AP due to the inherent characteristics of their network adapters. We would recommend enabling the Lock to AP feature to bind your wireless device to a specific AP.How to configure Lock to AP on Omada Controller | Omada Network Support

Hi,  @Leosimoni 
Thank you for providing the relevant information. 

To help us better troubleshoot the issue you are encountering, we would like to collect the following information from you:

1. Are the 4 EAPs connected via a Mesh network? If yes, could you please advise which EAP is configured as the Root AP?
2. Have you tested the connection with other client devices near the seond floor EAP? Do they also only connect to the first floor EAP610, or can they connect to the EAP610 on the second floor normally?
3.When did you first notice this issue? Was your device able to connect to the EAP610 on the second floor normally before this problem occurred?
4. Have you attempted swapping the positions of the first floor EAP610 and the EAP610 on the second floor for testing? Please feel free to disregard this question if it is inconvenient for you to remove and reposition the EAP.